Abstract

TtcA catalyzes the post-transcriptional thiolation of cytosine 32 in some tRNAs. The enzyme from Escherichia coli was homologously overexpressed in E. coli. The purified enzyme is a dimer containing an iron–sulfur cluster and displays activity in in vitro assays. The type and properties of the cluster were investigated using a combination of UV-visible absorption, EPR and Mössbauer spectroscopy, as well as by site-directed mutagenesis. These studies demonstrated that the TtcA enzyme contains a redox-active and oxygen-sensitive [4Fe-4S] cluster, chelated by only three cysteine residues and absolutely essential for activity. TtcA is unique tRNA-thiolating enzyme using an iron–sulfur cluster for catalyzing a non-redox reaction.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.